Spring unit



Oct. 8,- 1940- H. P. NORDMARK snuua mm Filed April 14, 1939 Patentedoer. s, 1940 v 2,217,290

UNITED STATES. PATENT, OFFICE SPRING UNIT Henry P. Nordmark, GrandRapids, Mich, assignor to American Seating Company, Grand Rapids, Mich,a corporation of New Jersey Application April 14, 1939, Serial No.267,791

Claims. (or. 155-479) The present invention relates to spring unitshooks I2 in the manner illustrated in Figure 1, and more particularlyspring units for supportthe springs are secured to the frame evenagainst ing chair seats or chair backs. pressure thereupon.

The primary objects of the instant invention It will thus be seen thatthe spring unit herein 5 are to provide improved means for securing ashown and described may be readily and con- 5 plurality of springs ofthe general character veniently assembled, is sturdy in constructionshown in Kaden Patent No. 2,002,399 within a and may be economicallymanufactured. seat or back frame of a chair; to provide an im- While butone specific embodiment of the inproved form of seat or back frame for achair vention has been herein shown and described, it

[0 having means for readily manually detachably will be understood thatcertaindetails of the securing a plurality of such springs therewith;construction shown may be altered or omitted and, to provide such a unitwhich is sturdy in without departing from the spirit of thisinvenconstruction and economical in manufacture. tion as the same isdefined by the following An illustrative embodiment of the invention isclaims. shown in the accompanying drawing, wherein: I claim: I 15 Figure1 is a perspective View of a, frame to 1. A supporting frame comprisinga rim havwhich springs of the general character shown I ing a pair ofits opposite sides each provided in the above identified patent havebeen secured; with a like. plurality of spaced and outwardly Figure 2 isan enlarged sectional view on line projecting tongues forming oppositelydisposed 2-2 of Figure 1; conpanion pairs of open spring retaininghooks, 20

Figure 3 is an enlarged sectional view on line and an outwardly bowedspring disposed between 3-3 of Figure 1; and each companion pair ofhooks whose opposite Figure 4 is a side elevational view of a singleends are detachably secured thereby, said springs spring of the typeshown in Figure 1, showing each having a permanent set on an arc ofgreater in full lines the approximate arc of curvature the curvaturethan the spring assumes after its as- 25 spring is caused to assume whensecured to its sembly with the frame.

frame and showing in dotted lines the arc of 2. A supporting framecomprising a stamped curvature of its permanent set prior to its assheetmetal rim having a pair of its opposite sembly with its frame. sideseach provided with a like plurality of spaced Referring then to thedrawing wherein like and outwardly projecting tongues struck there- 30parts of the unit shown are designated by the from to form oppositelydisposed companion pairs same numerals in the several views, the springof open spring retaining hooks, and an outwardly supporting frame for achair seat or back combowedspring disposed between each companion prisesthe rim generally designated 10, preferably pair of hooks whose oppositeends are detachformed of stamped sheet metal. ably secured thereby, saidsprings each having a 35 A pairof the opposite sides of the sheet metalpermanent set on an arc of greater curvature rim I!) are each providedwith an inwardly than the spring assumes after its assembly with flangedstrengthening portion H which flanged the frame. portions are eachreversely turned and equidis- 3. A frame for supporting a plurality ofspaced tantly notched along the ot er two opposite sides parallellydisposed springs comprising a stamped 40 thereof to form oppositelydisposed and equally sheet metal rim having a pair of its opposite sidesspaced companion pairs of spring retaining each provided with aninwardly flanged strengthn ues 0 hooks l2. ening portion which flangedportions are each A plurality of spaced parallelly disposed,outreversely turned and equidistantly notched along wardly bowedspringsl3, here shown as of the the other two opposite sides thereof to formoD- tortuous or sinuous type, are disposed between positely disposedcompanionpairs of open spring companion pairs of hooks to which theiropporetaining hooks, each companion pair of hooks site ends are secrued.Since these springs have being adapted to secure the opposite ends of ana permanent set onan arc of greater curvature outwardly bowed springhaving a permanent set than the spring assumes after its assembly withon an arc of greater curvature than the spring 50 'the frame Ill, eachspring when sprung from its assumes after its assembly with the frame.permanent set shown in dotted lines in Figure 4 4. A supporting framecomprising a stamped to the arc of curvature shown in full lines in thesheet metal rim having a pair of its opposite same view and thereaftersecured between and sides each provided with an inwardly flanged by anoppositely disposed companion pair of strengthening portion whichflanged portions 55 are, each reversely turned and equidistantly notchedalong the other two opposite sides thereof to form, oppositely disposedcompanion pairs of spring retaining hooks, and an outwardly bowed springdisposed between each companion pair of hooks whose opposite ends aresecured thereby, said springs each having a permanent set on an arc ofgreater curvature than the spring assumes after itsassembly with theframe.

5. A supporting frame comprising a rim having a pair of its oppositesides each provided with a like plurality of spaced and outwardlyprojecting ton ues forming oppositely disposed companion pairs of openspring retaining hooks, and an outwardly. bowed sinuous spring disposedbetween each companion pair of hooks whose opposite ends are detachablysecured thereby, said sinuous springs each having a permanent set on anarc of greater curvature than the spring assumes after'its assembly withthe frame;

HENRY P. NORDMARK

